// queue::swap
#include <bits/stdc++.h>
using namespace std;

int main ()
{
    queue<int> foo,bar;
    foo.push (10);foo.push(20); foo.push(30);
    bar.push (111); bar.push(222);
    cout<<"Current Size: "<<"\n";
    cout<<"foo size: "<<foo.size()<<" bar size: "<<bar.size()<<"\n";
    foo.swap(bar);
    cout<<"Swaped Size: "<<"\n";
    cout<<"foo size: "<<foo.size()<<" bar size: "<<bar.size()<<"\n";
  return 0;
}

